Fundamental theorem of calculus and definite integrals

Use the definite integral ∫ 𝑓(𝑥)𝑏 𝑎  𝑑𝑥 to determine the area under the curve 𝑦 = 𝑓(𝑥) between 𝑥 = 𝑎 and 𝑥 = 𝑏 if 𝑓(𝑥) > 0 over this interval.